The present invention relates to compositions and methods of bonding cord tire reinforcement to the conjugated diene based rubber of tire carcasses and the improved structures obtained thereby.
In the manufacture of cord reinforced tires, the cord is sometimes coated by the cord manufacturer with a material which improves adhesion of the cord to the rubber body of the tire. Cord free of adhesion promoter will be referred to as greige or uncoated. After the cord is received from the manufacturer in the form of a fabric, the general practice is to prepare the cord by applying a dip coating of a latex. The dip coating of the cord generally used contains a vinyl pyridine/styrene/butadiene terpolymer and a resorcinolformaldehyde (RF) resin. While these RF resins are quite effective in performing their desired function, the resorcinol component is expensive and often unobtainable in the quantities needed.
Materials in addition to RF resins have been used in the prior art to improve adhesion in special circumstances. For instance, a number of proprietary formulations of unknown composition are marketed for this purpose.